Prediction of PVT properties of pure and mixture of polymer melts using modified Ihm-Song-Mason equation of state
F. Yousefi, H. Karimi, R. Ghafarian Shirazi and M. Gomar
An accurate and efficient analytical equation of state (EOS) is developed for the prediction of volumetric properties of pure polymer melts and blends. To apply EOS, the second Virial coefficients B2, effective van der Waals co-volume, b and correction factor, α were determined. The second Virial coefficient was calculated from a two-parameter corresponding states correlation, which is constructed with two constants as scaling parameters, i.e., temperature (Tg) and density at glass transition point (ρg). The new correlations were used to predict the PVT behavior of pure polymer melts containing atactic polypropylene (a-PP), polyethylene oxide (PEO), polydimethylsiloxane (PDMS), poly styrene (PS), poly vinyl methyl ether (PVME), polycarbonate bisphenol- A (PC), poly butyl acrylate (PBA), poly vinyl chloride (PVC) and poly 2,6-dimethylphenylene oxide (PPO) and two blends such as PPO + PS and PS + PVME over the whole range of available temperature and pressure. The obtained mean of the deviations for all nine pure polymer melts was found to be of the order of 0.40%. In addition the calculated results of PPO + PS and PS + PVME have good agreement with the experimental data with absolute average deviations of 1.18% and 0.98%, respectively.
Keywords: Equation of state, Polymer melt, Blend, Glass temperature.